drivers/thermal/thermal_core.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  thermal.c - Generic Thermal Management Sysfs support.
   4  *
   5  *  Copyright (C) 2008 Intel Corp
   6  *  Copyright (C) 2008 Zhang Rui <rui.zhang@intel.com>
   7  *  Copyright (C) 2008 Sujith Thomas <sujith.thomas@intel.com>
   8  */
   9
  10 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
  11
  12 #include <linux/device.h>
  13 #include <linux/err.h>
  14 #include <linux/export.h>
  15 #include <linux/slab.h>
  16 #include <linux/kdev_t.h>
  17 #include <linux/idr.h>
  18 #include <linux/thermal.h>
  19 #include <linux/reboot.h>
  20 #include <linux/string.h>
  21 #include <linux/of.h>
  22 #include <linux/suspend.h>
  23
  24 #define CREATE_TRACE_POINTS
  25 #include "thermal_trace.h"
  26
  27 #include "thermal_core.h"
  28 #include "thermal_hwmon.h"
  29
  30 static DEFINE_IDA(thermal_tz_ida);
  31 static DEFINE_IDA(thermal_cdev_ida);
  32
  33 static LIST_HEAD(thermal_tz_list);
  34 static LIST_HEAD(thermal_cdev_list);
  35 static LIST_HEAD(thermal_governor_list);
  36
  37 static DEFINE_MUTEX(thermal_list_lock);
  38 static DEFINE_MUTEX(thermal_governor_lock);
  39
  40 static atomic_t in_suspend;
  41
  42 static struct thermal_governor *def_governor;
  43
  44 /*
  45  * Governor section: set of functions to handle thermal governors
  46  *
  47  * Functions to help in the life cycle of thermal governors within
  48  * the thermal core and by the thermal governor code.
  49  */
  50
  51 static struct thermal_governor *__find_governor(const char *name)
  52 {
  53         struct thermal_governor *pos;
  54
  55         if (!name || !name[0])
  56                 return def_governor;
  57
  58         list_for_each_entry(pos, &thermal_governor_list, governor_list)
  59                 if (!strncasecmp(name, pos->name, THERMAL_NAME_LENGTH))
  60                         return pos;
  61
  62         return NULL;
  63 }
  64
  65 /**
  66  * bind_previous_governor() - bind the previous governor of the thermal zone
  67  * @tz:         a valid pointer to a struct thermal_zone_device
  68  * @failed_gov_name:    the name of the governor that failed to register
  69  *
  70  * Register the previous governor of the thermal zone after a new
  71  * governor has failed to be bound.
  72  */
  73 static void bind_previous_governor(struct thermal_zone_device *tz,
  74                                    const char *failed_gov_name)
  75 {
  76         if (tz->governor && tz->governor->bind_to_tz) {
  77                 if (tz->governor->bind_to_tz(tz)) {
  78                         dev_err(&tz->device,
  79                                 "governor %s failed to bind and the previous one (%s) failed to bind again, thermal zone %s has no governor\n",
  80                                 failed_gov_name, tz->governor->name, tz->type);
  81                         tz->governor = NULL;
  82                 }
  83         }
  84 }
  85
  86 /**
  87  * thermal_set_governor() - Switch to another governor
  88  * @tz:         a valid pointer to a struct thermal_zone_device
  89  * @new_gov:    pointer to the new governor
  90  *
  91  * Change the governor of thermal zone @tz.
  92  *
  93  * Return: 0 on success, an error if the new governor's bind_to_tz() failed.
  94  */
  95 static int thermal_set_governor(struct thermal_zone_device *tz,
  96                                 struct thermal_governor *new_gov)
  97 {
  98         int ret = 0;
  99
 100         if (tz->governor && tz->governor->unbind_from_tz)
 101                 tz->governor->unbind_from_tz(tz);
 102
 103         if (new_gov && new_gov->bind_to_tz) {
 104                 ret = new_gov->bind_to_tz(tz);
 105                 if (ret) {
 106                         bind_previous_governor(tz, new_gov->name);
 107
 108                         return ret;
 109                 }
 110         }
 111
 112         tz->governor = new_gov;
 113
 114         return ret;
 115 }
 116
 117 int thermal_register_governor(struct thermal_governor *governor)
 118 {
 119         int err;
 120         const char *name;
 121         struct thermal_zone_device *pos;
 122
 123         if (!governor)
 124                 return -EINVAL;
 125
 126         mutex_lock(&thermal_governor_lock);
 127
 128         err = -EBUSY;
 129         if (!__find_governor(governor->name)) {
 130                 bool match_default;
 131
 132                 err = 0;
 133                 list_add(&governor->governor_list, &thermal_governor_list);
 134                 match_default = !strncmp(governor->name,
 135                                          DEFAULT_THERMAL_GOVERNOR,
 136                                          THERMAL_NAME_LENGTH);
 137
 138                 if (!def_governor && match_default)
 139                         def_governor = governor;
 140         }
 141
 142         mutex_lock(&thermal_list_lock);
 143
 144         list_for_each_entry(pos, &thermal_tz_list, node) {
 145                 /*
 146                  * only thermal zones with specified tz->tzp->governor_name
 147                  * may run with tz->govenor unset
 148                  */
 149                 if (pos->governor)
 150                         continue;
 151
 152                 name = pos->tzp->governor_name;
 153
 154                 if (!strncasecmp(name, governor->name, THERMAL_NAME_LENGTH)) {
 155                         int ret;
 156
 157                         ret = thermal_set_governor(pos, governor);
 158                         if (ret)
 159                                 dev_err(&pos->device,
 160                                         "Failed to set governor %s for thermal zone %s: %d\n",
 161                                         governor->name, pos->type, ret);
 162                 }
 163         }
 164
 165         mutex_unlock(&thermal_list_lock);
 166         mutex_unlock(&thermal_governor_lock);
 167
 168         return err;
 169 }
 170
 171 void thermal_unregister_governor(struct thermal_governor *governor)
 172 {
 173         struct thermal_zone_device *pos;
 174
 175         if (!governor)
 176                 return;
 177
 178         mutex_lock(&thermal_governor_lock);
 179
 180         if (!__find_governor(governor->name))
 181                 goto exit;
 182
 183         mutex_lock(&thermal_list_lock);
 184
 185         list_for_each_entry(pos, &thermal_tz_list, node) {
 186                 if (!strncasecmp(pos->governor->name, governor->name,
 187                                  THERMAL_NAME_LENGTH))
 188                         thermal_set_governor(pos, NULL);
 189         }
 190
 191         mutex_unlock(&thermal_list_lock);
 192         list_del(&governor->governor_list);
 193 exit:
 194         mutex_unlock(&thermal_governor_lock);
 195 }
 196
 197 int thermal_zone_device_set_policy(struct thermal_zone_device *tz,
 198                                    char *policy)
 199 {
 200         struct thermal_governor *gov;
 201         int ret = -EINVAL;
 202
 203         mutex_lock(&thermal_governor_lock);
 204         mutex_lock(&tz->lock);
 205
 206         if (!device_is_registered(&tz->device))
 207                 goto exit;
 208
 209         gov = __find_governor(strim(policy));
 210         if (!gov)
 211                 goto exit;
 212
 213         ret = thermal_set_governor(tz, gov);
 214
 215 exit:
 216         mutex_unlock(&tz->lock);
 217         mutex_unlock(&thermal_governor_lock);
 218
 219         thermal_notify_tz_gov_change(tz->id, policy);
 220
 221         return ret;
 222 }
 223
 224 int thermal_build_list_of_policies(char *buf)
 225 {
 226         struct thermal_governor *pos;
 227         ssize_t count = 0;
 228
 229         mutex_lock(&thermal_governor_lock);
 230
 231         list_for_each_entry(pos, &thermal_governor_list, governor_list) {
 232                 count += sysfs_emit_at(buf, count, "%s ", pos->name);
 233         }
 234         count += sysfs_emit_at(buf, count, "\n");
 235
 236         mutex_unlock(&thermal_governor_lock);
 237
 238         return count;
 239 }
 240
 241 static void __init thermal_unregister_governors(void)
 242 {
 243         struct thermal_governor **governor;
 244
 245         for_each_governor_table(governor)
 246                 thermal_unregister_governor(*governor);
 247 }
 248
 249 static int __init thermal_register_governors(void)
 250 {
 251         int ret = 0;
 252         struct thermal_governor **governor;
 253
 254         for_each_governor_table(governor) {
 255                 ret = thermal_register_governor(*governor);
 256                 if (ret) {
 257                         pr_err("Failed to register governor: '%s'",
 258                                (*governor)->name);
 259                         break;
 260                 }
 261
 262                 pr_info("Registered thermal governor '%s'",
 263                         (*governor)->name);
 264         }
 265
 266         if (ret) {
 267                 struct thermal_governor **gov;
 268
 269                 for_each_governor_table(gov) {
 270                         if (gov == governor)
 271                                 break;
 272                         thermal_unregister_governor(*gov);
 273                 }
 274         }
 275
 276         return ret;
 277 }
 278
 279 /*
 280  * Zone update section: main control loop applied to each zone while monitoring
 281  *
 282  * in polling mode. The monitoring is done using a workqueue.
 283  * Same update may be done on a zone by calling thermal_zone_device_update().
 284  *
 285  * An update means:
 286  * - Non-critical trips will invoke the governor responsible for that zone;
 287  * - Hot trips will produce a notification to userspace;
 288  * - Critical trip point will cause a system shutdown.
 289  */
 290 static void thermal_zone_device_set_polling(struct thermal_zone_device *tz,
 291                                             unsigned long delay)
 292 {
 293         if (delay)
 294                 mod_delayed_work(system_freezable_power_efficient_wq,
 295                                  &tz->poll_queue, delay);
 296         else
 297                 cancel_delayed_work(&tz->poll_queue);
 298 }
 299
 300 static void monitor_thermal_zone(struct thermal_zone_device *tz)
 301 {
 302         if (tz->mode != THERMAL_DEVICE_ENABLED)
 303                 thermal_zone_device_set_polling(tz, 0);
 304         else if (tz->passive)
 305                 thermal_zone_device_set_polling(tz, tz->passive_delay_jiffies);
 306         else if (tz->polling_delay_jiffies)
 307                 thermal_zone_device_set_polling(tz, tz->polling_delay_jiffies);
 308 }
 309
 310 static void handle_non_critical_trips(struct thermal_zone_device *tz,
 311                                       const struct thermal_trip *trip)
 312 {
 313         tz->governor ? tz->governor->throttle(tz, trip) :
 314                        def_governor->throttle(tz, trip);
 315 }
 316
 317 void thermal_zone_device_critical(struct thermal_zone_device *tz)
 318 {
 319         /*
 320          * poweroff_delay_ms must be a carefully profiled positive value.
 321          * Its a must for forced_emergency_poweroff_work to be scheduled.
 322          */
 323         int poweroff_delay_ms = CONFIG_THERMAL_EMERGENCY_POWEROFF_DELAY_MS;
 324
 325         dev_emerg(&tz->device, "%s: critical temperature reached, "
 326                   "shutting down\n", tz->type);
 327
 328         hw_protection_shutdown("Temperature too high", poweroff_delay_ms);
 329 }
 330 EXPORT_SYMBOL(thermal_zone_device_critical);
 331
 332 static void handle_critical_trips(struct thermal_zone_device *tz,
 333                                   const struct thermal_trip *trip)
 334 {
 335         /* If we have not crossed the trip_temp, we do not care. */
 336         if (trip->temperature <= 0 || tz->temperature < trip->temperature)
 337                 return;
 338
 339         trace_thermal_zone_trip(tz, thermal_zone_trip_id(tz, trip), trip->type);
 340
 341         if (trip->type == THERMAL_TRIP_CRITICAL)
 342                 tz->ops->critical(tz);
 343         else if (tz->ops->hot)
 344                 tz->ops->hot(tz);
 345 }
 346
 347 static void handle_thermal_trip(struct thermal_zone_device *tz,
 348                                 const struct thermal_trip *trip)
 349 {
 350         if (trip->temperature == THERMAL_TEMP_INVALID)
 351                 return;
 352
 353         if (tz->last_temperature != THERMAL_TEMP_INVALID) {
 354                 if (tz->last_temperature < trip->temperature &&
 355                     tz->temperature >= trip->temperature)
 356                         thermal_notify_tz_trip_up(tz->id,
 357                                                   thermal_zone_trip_id(tz, trip),
 358                                                   tz->temperature);
 359                 if (tz->last_temperature >= trip->temperature &&
 360                     tz->temperature < trip->temperature - trip->hysteresis)
 361                         thermal_notify_tz_trip_down(tz->id,
 362                                                     thermal_zone_trip_id(tz, trip),
 363                                                     tz->temperature);
 364         }
 365
 366         if (trip->type == THERMAL_TRIP_CRITICAL || trip->type == THERMAL_TRIP_HOT)
 367                 handle_critical_trips(tz, trip);
 368         else
 369                 handle_non_critical_trips(tz, trip);
 370 }
 371
 372 static void update_temperature(struct thermal_zone_device *tz)
 373 {
 374         int temp, ret;
 375
 376         ret = __thermal_zone_get_temp(tz, &temp);
 377         if (ret) {
 378                 if (ret != -EAGAIN)
 379                         dev_warn(&tz->device,
 380                                  "failed to read out thermal zone (%d)\n",
 381                                  ret);
 382                 return;
 383         }
 384
 385         tz->last_temperature = tz->temperature;
 386         tz->temperature = temp;
 387
 388         trace_thermal_temperature(tz);
 389
 390         thermal_genl_sampling_temp(tz->id, temp);
 391 }
 392
 393 static void thermal_zone_device_init(struct thermal_zone_device *tz)
 394 {
 395         struct thermal_instance *pos;
 396         tz->temperature = THERMAL_TEMP_INVALID;
 397         tz->prev_low_trip = -INT_MAX;
 398         tz->prev_high_trip = INT_MAX;
 399         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 400                 pos->initialized = false;
 401 }
 402
 403 void __thermal_zone_device_update(struct thermal_zone_device *tz,
 404                                   enum thermal_notify_event event)
 405 {
 406         const struct thermal_trip *trip;
 407
 408         if (atomic_read(&in_suspend))
 409                 return;
 410
 411         if (WARN_ONCE(!tz->ops->get_temp,
 412                       "'%s' must not be called without 'get_temp' ops set\n",
 413                       __func__))
 414                 return;
 415
 416         if (!thermal_zone_device_is_enabled(tz))
 417                 return;
 418
 419         update_temperature(tz);
 420
 421         __thermal_zone_set_trips(tz);
 422
 423         tz->notify_event = event;
 424
 425         for_each_trip(tz, trip)
 426                 handle_thermal_trip(tz, trip);
 427
 428         monitor_thermal_zone(tz);
 429 }
 430
 431 static int thermal_zone_device_set_mode(struct thermal_zone_device *tz,
 432                                         enum thermal_device_mode mode)
 433 {
 434         int ret = 0;
 435
 436         mutex_lock(&tz->lock);
 437
 438         /* do nothing if mode isn't changing */
 439         if (mode == tz->mode) {
 440                 mutex_unlock(&tz->lock);
 441
 442                 return ret;
 443         }
 444
 445         if (!device_is_registered(&tz->device)) {
 446                 mutex_unlock(&tz->lock);
 447
 448                 return -ENODEV;
 449         }
 450
 451         if (tz->ops->change_mode)
 452                 ret = tz->ops->change_mode(tz, mode);
 453
 454         if (!ret)
 455                 tz->mode = mode;
 456
 457         __thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 458
 459         mutex_unlock(&tz->lock);
 460
 461         if (mode == THERMAL_DEVICE_ENABLED)
 462                 thermal_notify_tz_enable(tz->id);
 463         else
 464                 thermal_notify_tz_disable(tz->id);
 465
 466         return ret;
 467 }
 468
 469 int thermal_zone_device_enable(struct thermal_zone_device *tz)
 470 {
 471         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_ENABLED);
 472 }
 473 EXPORT_SYMBOL_GPL(thermal_zone_device_enable);
 474
 475 int thermal_zone_device_disable(struct thermal_zone_device *tz)
 476 {
 477         return thermal_zone_device_set_mode(tz, THERMAL_DEVICE_DISABLED);
 478 }
 479 EXPORT_SYMBOL_GPL(thermal_zone_device_disable);
 480
 481 int thermal_zone_device_is_enabled(struct thermal_zone_device *tz)
 482 {
 483         lockdep_assert_held(&tz->lock);
 484
 485         return tz->mode == THERMAL_DEVICE_ENABLED;
 486 }
 487
 488 void thermal_zone_device_update(struct thermal_zone_device *tz,
 489                                 enum thermal_notify_event event)
 490 {
 491         mutex_lock(&tz->lock);
 492         if (device_is_registered(&tz->device))
 493                 __thermal_zone_device_update(tz, event);
 494         mutex_unlock(&tz->lock);
 495 }
 496 EXPORT_SYMBOL_GPL(thermal_zone_device_update);
 497
 498 static void thermal_zone_device_check(struct work_struct *work)
 499 {
 500         struct thermal_zone_device *tz = container_of(work, struct
 501                                                       thermal_zone_device,
 502                                                       poll_queue.work);
 503         thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
 504 }
 505
 506 int for_each_thermal_governor(int (*cb)(struct thermal_governor *, void *),
 507                               void *data)
 508 {
 509         struct thermal_governor *gov;
 510         int ret = 0;
 511
 512         mutex_lock(&thermal_governor_lock);
 513         list_for_each_entry(gov, &thermal_governor_list, governor_list) {
 514                 ret = cb(gov, data);
 515                 if (ret)
 516                         break;
 517         }
 518         mutex_unlock(&thermal_governor_lock);
 519
 520         return ret;
 521 }
 522
 523 int for_each_thermal_cooling_device(int (*cb)(struct thermal_cooling_device *,
 524                                               void *), void *data)
 525 {
 526         struct thermal_cooling_device *cdev;
 527         int ret = 0;
 528
 529         mutex_lock(&thermal_list_lock);
 530         list_for_each_entry(cdev, &thermal_cdev_list, node) {
 531                 ret = cb(cdev, data);
 532                 if (ret)
 533                         break;
 534         }
 535         mutex_unlock(&thermal_list_lock);
 536
 537         return ret;
 538 }
 539
 540 int for_each_thermal_zone(int (*cb)(struct thermal_zone_device *, void *),
 541                           void *data)
 542 {
 543         struct thermal_zone_device *tz;
 544         int ret = 0;
 545
 546         mutex_lock(&thermal_list_lock);
 547         list_for_each_entry(tz, &thermal_tz_list, node) {
 548                 ret = cb(tz, data);
 549                 if (ret)
 550                         break;
 551         }
 552         mutex_unlock(&thermal_list_lock);
 553
 554         return ret;
 555 }
 556
 557 struct thermal_zone_device *thermal_zone_get_by_id(int id)
 558 {
 559         struct thermal_zone_device *tz, *match = NULL;
 560
 561         mutex_lock(&thermal_list_lock);
 562         list_for_each_entry(tz, &thermal_tz_list, node) {
 563                 if (tz->id == id) {
 564                         match = tz;
 565                         break;
 566                 }
 567         }
 568         mutex_unlock(&thermal_list_lock);
 569
 570         return match;
 571 }
 572
 573 /*
 574  * Device management section: cooling devices, zones devices, and binding
 575  *
 576  * Set of functions provided by the thermal core for:
 577  * - cooling devices lifecycle: registration, unregistration,
 578  *                              binding, and unbinding.
 579  * - thermal zone devices lifecycle: registration, unregistration,
 580  *                                   binding, and unbinding.
 581  */
 582
 583 /**
 584  * thermal_bind_cdev_to_trip - bind a cooling device to a thermal zone
 585  * @tz:         pointer to struct thermal_zone_device
 586  * @trip:       trip point the cooling devices is associated with in this zone.
 587  * @cdev:       pointer to struct thermal_cooling_device
 588  * @upper:      the Maximum cooling state for this trip point.
 589  *              THERMAL_NO_LIMIT means no upper limit,
 590  *              and the cooling device can be in max_state.
 591  * @lower:      the Minimum cooling state can be used for this trip point.
 592  *              THERMAL_NO_LIMIT means no lower limit,
 593  *              and the cooling device can be in cooling state 0.
 594  * @weight:     The weight of the cooling device to be bound to the
 595  *              thermal zone. Use THERMAL_WEIGHT_DEFAULT for the
 596  *              default value
 597  *
 598  * This interface function bind a thermal cooling device to the certain trip
 599  * point of a thermal zone device.
 600  * This function is usually called in the thermal zone device .bind callback.
 601  *
 602  * Return: 0 on success, the proper error value otherwise.
 603  */
 604 int thermal_bind_cdev_to_trip(struct thermal_zone_device *tz,
 605                                      const struct thermal_trip *trip,
 606                                      struct thermal_cooling_device *cdev,
 607                                      unsigned long upper, unsigned long lower,
 608                                      unsigned int weight)
 609 {
 610         struct thermal_instance *dev;
 611         struct thermal_instance *pos;
 612         struct thermal_zone_device *pos1;
 613         struct thermal_cooling_device *pos2;
 614         bool upper_no_limit;
 615         int result;
 616
 617         list_for_each_entry(pos1, &thermal_tz_list, node) {
 618                 if (pos1 == tz)
 619                         break;
 620         }
 621         list_for_each_entry(pos2, &thermal_cdev_list, node) {
 622                 if (pos2 == cdev)
 623                         break;
 624         }
 625
 626         if (tz != pos1 || cdev != pos2)
 627                 return -EINVAL;
 628
 629         /* lower default 0, upper default max_state */
 630         lower = lower == THERMAL_NO_LIMIT ? 0 : lower;
 631
 632         if (upper == THERMAL_NO_LIMIT) {
 633                 upper = cdev->max_state;
 634                 upper_no_limit = true;
 635         } else {
 636                 upper_no_limit = false;
 637         }
 638
 639         if (lower > upper || upper > cdev->max_state)
 640                 return -EINVAL;
 641
 642         dev = kzalloc(sizeof(*dev), GFP_KERNEL);
 643         if (!dev)
 644                 return -ENOMEM;
 645         dev->tz = tz;
 646         dev->cdev = cdev;
 647         dev->trip = trip;
 648         dev->upper = upper;
 649         dev->upper_no_limit = upper_no_limit;
 650         dev->lower = lower;
 651         dev->target = THERMAL_NO_TARGET;
 652         dev->weight = weight;
 653
 654         result = ida_alloc(&tz->ida, GFP_KERNEL);
 655         if (result < 0)
 656                 goto free_mem;
 657
 658         dev->id = result;
 659         sprintf(dev->name, "cdev%d", dev->id);
 660         result =
 661             sysfs_create_link(&tz->device.kobj, &cdev->device.kobj, dev->name);
 662         if (result)
 663                 goto release_ida;
 664
 665         snprintf(dev->attr_name, sizeof(dev->attr_name), "cdev%d_trip_point",
 666                  dev->id);
 667         sysfs_attr_init(&dev->attr.attr);
 668         dev->attr.attr.name = dev->attr_name;
 669         dev->attr.attr.mode = 0444;
 670         dev->attr.show = trip_point_show;
 671         result = device_create_file(&tz->device, &dev->attr);
 672         if (result)
 673                 goto remove_symbol_link;
 674
 675         snprintf(dev->weight_attr_name, sizeof(dev->weight_attr_name),
 676                  "cdev%d_weight", dev->id);
 677         sysfs_attr_init(&dev->weight_attr.attr);
 678         dev->weight_attr.attr.name = dev->weight_attr_name;
 679         dev->weight_attr.attr.mode = S_IWUSR | S_IRUGO;
 680         dev->weight_attr.show = weight_show;
 681         dev->weight_attr.store = weight_store;
 682         result = device_create_file(&tz->device, &dev->weight_attr);
 683         if (result)
 684                 goto remove_trip_file;
 685
 686         mutex_lock(&tz->lock);
 687         mutex_lock(&cdev->lock);
 688         list_for_each_entry(pos, &tz->thermal_instances, tz_node)
 689                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 690                         result = -EEXIST;
 691                         break;
 692                 }
 693         if (!result) {
 694                 list_add_tail(&dev->tz_node, &tz->thermal_instances);
 695                 list_add_tail(&dev->cdev_node, &cdev->thermal_instances);
 696                 atomic_set(&tz->need_update, 1);
 697         }
 698         mutex_unlock(&cdev->lock);
 699         mutex_unlock(&tz->lock);
 700
 701         if (!result)
 702                 return 0;
 703
 704         device_remove_file(&tz->device, &dev->weight_attr);
 705 remove_trip_file:
 706         device_remove_file(&tz->device, &dev->attr);
 707 remove_symbol_link:
 708         sysfs_remove_link(&tz->device.kobj, dev->name);
 709 release_ida:
 710         ida_free(&tz->ida, dev->id);
 711 free_mem:
 712         kfree(dev);
 713         return result;
 714 }
 715 EXPORT_SYMBOL_GPL(thermal_bind_cdev_to_trip);
 716
 717 int thermal_zone_bind_cooling_device(struct thermal_zone_device *tz,
 718                                      int trip_index,
 719                                      struct thermal_cooling_device *cdev,
 720                                      unsigned long upper, unsigned long lower,
 721                                      unsigned int weight)
 722 {
 723         if (trip_index < 0 || trip_index >= tz->num_trips)
 724                 return -EINVAL;
 725
 726         return thermal_bind_cdev_to_trip(tz, &tz->trips[trip_index], cdev,
 727                                          upper, lower, weight);
 728 }
 729 EXPORT_SYMBOL_GPL(thermal_zone_bind_cooling_device);
 730
 731 /**
 732  * thermal_unbind_cdev_from_trip - unbind a cooling device from a thermal zone.
 733  * @tz:         pointer to a struct thermal_zone_device.
 734  * @trip:       trip point the cooling devices is associated with in this zone.
 735  * @cdev:       pointer to a struct thermal_cooling_device.
 736  *
 737  * This interface function unbind a thermal cooling device from the certain
 738  * trip point of a thermal zone device.
 739  * This function is usually called in the thermal zone device .unbind callback.
 740  *
 741  * Return: 0 on success, the proper error value otherwise.
 742  */
 743 int thermal_unbind_cdev_from_trip(struct thermal_zone_device *tz,
 744                                   const struct thermal_trip *trip,
 745                                   struct thermal_cooling_device *cdev)
 746 {
 747         struct thermal_instance *pos, *next;
 748
 749         mutex_lock(&tz->lock);
 750         mutex_lock(&cdev->lock);
 751         list_for_each_entry_safe(pos, next, &tz->thermal_instances, tz_node) {
 752                 if (pos->tz == tz && pos->trip == trip && pos->cdev == cdev) {
 753                         list_del(&pos->tz_node);
 754                         list_del(&pos->cdev_node);
 755                         mutex_unlock(&cdev->lock);
 756                         mutex_unlock(&tz->lock);
 757                         goto unbind;
 758                 }
 759         }
 760         mutex_unlock(&cdev->lock);
 761         mutex_unlock(&tz->lock);
 762
 763         return -ENODEV;
 764
 765 unbind:
 766         device_remove_file(&tz->device, &pos->weight_attr);
 767         device_remove_file(&tz->device, &pos->attr);
 768         sysfs_remove_link(&tz->device.kobj, pos->name);
 769         ida_free(&tz->ida, pos->id);
 770         kfree(pos);
 771         return 0;
 772 }
 773 EXPORT_SYMBOL_GPL(thermal_unbind_cdev_from_trip);
 774
 775 int thermal_zone_unbind_cooling_device(struct thermal_zone_device *tz,
 776                                        int trip_index,
 777                                        struct thermal_cooling_device *cdev)
 778 {
 779         if (trip_index < 0 || trip_index >= tz->num_trips)
 780                 return -EINVAL;
 781
 782         return thermal_unbind_cdev_from_trip(tz, &tz->trips[trip_index], cdev);
 783 }
 784 EXPORT_SYMBOL_GPL(thermal_zone_unbind_cooling_device);
 785
 786 static void thermal_release(struct device *dev)
 787 {
 788         struct thermal_zone_device *tz;
 789         struct thermal_cooling_device *cdev;
 790
 791         if (!strncmp(dev_name(dev), "thermal_zone",
 792                      sizeof("thermal_zone") - 1)) {
 793                 tz = to_thermal_zone(dev);
 794                 thermal_zone_destroy_device_groups(tz);
 795                 mutex_destroy(&tz->lock);
 796                 kfree(tz);
 797         } else if (!strncmp(dev_name(dev), "cooling_device",
 798                             sizeof("cooling_device") - 1)) {
 799                 cdev = to_cooling_device(dev);
 800                 thermal_cooling_device_destroy_sysfs(cdev);
 801                 kfree(cdev->type);
 802                 ida_free(&thermal_cdev_ida, cdev->id);
 803                 kfree(cdev);
 804         }
 805 }
 806
 807 static struct class *thermal_class;
 808
 809 static inline
 810 void print_bind_err_msg(struct thermal_zone_device *tz,
 811                         struct thermal_cooling_device *cdev, int ret)
 812 {
 813         dev_err(&tz->device, "binding zone %s with cdev %s failed:%d\n",
 814                 tz->type, cdev->type, ret);
 815 }
 816
 817 static void bind_cdev(struct thermal_cooling_device *cdev)
 818 {
 819         int ret;
 820         struct thermal_zone_device *pos = NULL;
 821
 822         list_for_each_entry(pos, &thermal_tz_list, node) {
 823                 if (pos->ops->bind) {
 824                         ret = pos->ops->bind(pos, cdev);
 825                         if (ret)
 826                                 print_bind_err_msg(pos, cdev, ret);
 827                 }
 828         }
 829 }
 830
 831 /**
 832  * __thermal_cooling_device_register() - register a new thermal cooling device
 833  * @np:         a pointer to a device tree node.
 834  * @type:       the thermal cooling device type.
 835  * @devdata:    device private data.
 836  * @ops:                standard thermal cooling devices callbacks.
 837  *
 838  * This interface function adds a new thermal cooling device (fan/processor/...)
 839  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 840  * to all the thermal zone devices registered at the same time.
 841  * It also gives the opportunity to link the cooling device to a device tree
 842  * node, so that it can be bound to a thermal zone created out of device tree.
 843  *
 844  * Return: a pointer to the created struct thermal_cooling_device or an
 845  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 846  */
 847 static struct thermal_cooling_device *
 848 __thermal_cooling_device_register(struct device_node *np,
 849                                   const char *type, void *devdata,
 850                                   const struct thermal_cooling_device_ops *ops)
 851 {
 852         struct thermal_cooling_device *cdev;
 853         struct thermal_zone_device *pos = NULL;
 854         int id, ret;
 855
 856         if (!ops || !ops->get_max_state || !ops->get_cur_state ||
 857             !ops->set_cur_state)
 858                 return ERR_PTR(-EINVAL);
 859
 860         if (!thermal_class)
 861                 return ERR_PTR(-ENODEV);
 862
 863         cdev = kzalloc(sizeof(*cdev), GFP_KERNEL);
 864         if (!cdev)
 865                 return ERR_PTR(-ENOMEM);
 866
 867         ret = ida_alloc(&thermal_cdev_ida, GFP_KERNEL);
 868         if (ret < 0)
 869                 goto out_kfree_cdev;
 870         cdev->id = ret;
 871         id = ret;
 872
 873         cdev->type = kstrdup(type ? type : "", GFP_KERNEL);
 874         if (!cdev->type) {
 875                 ret = -ENOMEM;
 876                 goto out_ida_remove;
 877         }
 878
 879         mutex_init(&cdev->lock);
 880         INIT_LIST_HEAD(&cdev->thermal_instances);
 881         cdev->np = np;
 882         cdev->ops = ops;
 883         cdev->updated = false;
 884         cdev->device.class = thermal_class;
 885         cdev->devdata = devdata;
 886
 887         ret = cdev->ops->get_max_state(cdev, &cdev->max_state);
 888         if (ret)
 889                 goto out_cdev_type;
 890
 891         thermal_cooling_device_setup_sysfs(cdev);
 892
 893         ret = dev_set_name(&cdev->device, "cooling_device%d", cdev->id);
 894         if (ret)
 895                 goto out_cooling_dev;
 896
 897         ret = device_register(&cdev->device);
 898         if (ret) {
 899                 /* thermal_release() handles rest of the cleanup */
 900                 put_device(&cdev->device);
 901                 return ERR_PTR(ret);
 902         }
 903
 904         /* Add 'this' new cdev to the global cdev list */
 905         mutex_lock(&thermal_list_lock);
 906
 907         list_add(&cdev->node, &thermal_cdev_list);
 908
 909         /* Update binding information for 'this' new cdev */
 910         bind_cdev(cdev);
 911
 912         list_for_each_entry(pos, &thermal_tz_list, node)
 913                 if (atomic_cmpxchg(&pos->need_update, 1, 0))
 914                         thermal_zone_device_update(pos,
 915                                                    THERMAL_EVENT_UNSPECIFIED);
 916
 917         mutex_unlock(&thermal_list_lock);
 918
 919         return cdev;
 920
 921 out_cooling_dev:
 922         thermal_cooling_device_destroy_sysfs(cdev);
 923 out_cdev_type:
 924         kfree(cdev->type);
 925 out_ida_remove:
 926         ida_free(&thermal_cdev_ida, id);
 927 out_kfree_cdev:
 928         kfree(cdev);
 929         return ERR_PTR(ret);
 930 }
 931
 932 /**
 933  * thermal_cooling_device_register() - register a new thermal cooling device
 934  * @type:       the thermal cooling device type.
 935  * @devdata:    device private data.
 936  * @ops:                standard thermal cooling devices callbacks.
 937  *
 938  * This interface function adds a new thermal cooling device (fan/processor/...)
 939  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 940  * to all the thermal zone devices registered at the same time.
 941  *
 942  * Return: a pointer to the created struct thermal_cooling_device or an
 943  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 944  */
 945 struct thermal_cooling_device *
 946 thermal_cooling_device_register(const char *type, void *devdata,
 947                                 const struct thermal_cooling_device_ops *ops)
 948 {
 949         return __thermal_cooling_device_register(NULL, type, devdata, ops);
 950 }
 951 EXPORT_SYMBOL_GPL(thermal_cooling_device_register);
 952
 953 /**
 954  * thermal_of_cooling_device_register() - register an OF thermal cooling device
 955  * @np:         a pointer to a device tree node.
 956  * @type:       the thermal cooling device type.
 957  * @devdata:    device private data.
 958  * @ops:                standard thermal cooling devices callbacks.
 959  *
 960  * This function will register a cooling device with device tree node reference.
 961  * This interface function adds a new thermal cooling device (fan/processor/...)
 962  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 963  * to all the thermal zone devices registered at the same time.
 964  *
 965  * Return: a pointer to the created struct thermal_cooling_device or an
 966  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 967  */
 968 struct thermal_cooling_device *
 969 thermal_of_cooling_device_register(struct device_node *np,
 970                                    const char *type, void *devdata,
 971                                    const struct thermal_cooling_device_ops *ops)
 972 {
 973         return __thermal_cooling_device_register(np, type, devdata, ops);
 974 }
 975 EXPORT_SYMBOL_GPL(thermal_of_cooling_device_register);
 976
 977 static void thermal_cooling_device_release(struct device *dev, void *res)
 978 {
 979         thermal_cooling_device_unregister(
 980                                 *(struct thermal_cooling_device **)res);
 981 }
 982
 983 /**
 984  * devm_thermal_of_cooling_device_register() - register an OF thermal cooling
 985  *                                             device
 986  * @dev:        a valid struct device pointer of a sensor device.
 987  * @np:         a pointer to a device tree node.
 988  * @type:       the thermal cooling device type.
 989  * @devdata:    device private data.
 990  * @ops:        standard thermal cooling devices callbacks.
 991  *
 992  * This function will register a cooling device with device tree node reference.
 993  * This interface function adds a new thermal cooling device (fan/processor/...)
 994  * to /sys/class/thermal/ folder as cooling_device[0-*]. It tries to bind itself
 995  * to all the thermal zone devices registered at the same time.
 996  *
 997  * Return: a pointer to the created struct thermal_cooling_device or an
 998  * ERR_PTR. Caller must check return value with IS_ERR*() helpers.
 999  */
1000 struct thermal_cooling_device *
1001 devm_thermal_of_cooling_device_register(struct device *dev,
1002                                 struct device_node *np,
1003                                 char *type, void *devdata,
1004                                 const struct thermal_cooling_device_ops *ops)
1005 {
1006         struct thermal_cooling_device **ptr, *tcd;
1007
1008         ptr = devres_alloc(thermal_cooling_device_release, sizeof(*ptr),
1009                            GFP_KERNEL);
1010         if (!ptr)
1011                 return ERR_PTR(-ENOMEM);
1012
1013         tcd = __thermal_cooling_device_register(np, type, devdata, ops);
1014         if (IS_ERR(tcd)) {
1015                 devres_free(ptr);
1016                 return tcd;
1017         }
1018
1019         *ptr = tcd;
1020         devres_add(dev, ptr);
1021
1022         return tcd;
1023 }
1024 EXPORT_SYMBOL_GPL(devm_thermal_of_cooling_device_register);
1025
1026 static bool thermal_cooling_device_present(struct thermal_cooling_device *cdev)
1027 {
1028         struct thermal_cooling_device *pos = NULL;
1029
1030         list_for_each_entry(pos, &thermal_cdev_list, node) {
1031                 if (pos == cdev)
1032                         return true;
1033         }
1034
1035         return false;
1036 }
1037
1038 /**
1039  * thermal_cooling_device_update - Update a cooling device object
1040  * @cdev: Target cooling device.
1041  *
1042  * Update @cdev to reflect a change of the underlying hardware or platform.
1043  *
1044  * Must be called when the maximum cooling state of @cdev becomes invalid and so
1045  * its .get_max_state() callback needs to be run to produce the new maximum
1046  * cooling state value.
1047  */
1048 void thermal_cooling_device_update(struct thermal_cooling_device *cdev)
1049 {
1050         struct thermal_instance *ti;
1051         unsigned long state;
1052
1053         if (IS_ERR_OR_NULL(cdev))
1054                 return;
1055
1056         /*
1057          * Hold thermal_list_lock throughout the update to prevent the device
1058          * from going away while being updated.
1059          */
1060         mutex_lock(&thermal_list_lock);
1061
1062         if (!thermal_cooling_device_present(cdev))
1063                 goto unlock_list;
1064
1065         /*
1066          * Update under the cdev lock to prevent the state from being set beyond
1067          * the new limit concurrently.
1068          */
1069         mutex_lock(&cdev->lock);
1070
1071         if (cdev->ops->get_max_state(cdev, &cdev->max_state))
1072                 goto unlock;
1073
1074         thermal_cooling_device_stats_reinit(cdev);
1075
1076         list_for_each_entry(ti, &cdev->thermal_instances, cdev_node) {
1077                 if (ti->upper == cdev->max_state)
1078                         continue;
1079
1080                 if (ti->upper < cdev->max_state) {
1081                         if (ti->upper_no_limit)
1082                                 ti->upper = cdev->max_state;
1083
1084                         continue;
1085                 }
1086
1087                 ti->upper = cdev->max_state;
1088                 if (ti->lower > ti->upper)
1089                         ti->lower = ti->upper;
1090
1091                 if (ti->target == THERMAL_NO_TARGET)
1092                         continue;
1093
1094                 if (ti->target > ti->upper)
1095                         ti->target = ti->upper;
1096         }
1097
1098         if (cdev->ops->get_cur_state(cdev, &state) || state > cdev->max_state)
1099                 goto unlock;
1100
1101         thermal_cooling_device_stats_update(cdev, state);
1102
1103 unlock:
1104         mutex_unlock(&cdev->lock);
1105
1106 unlock_list:
1107         mutex_unlock(&thermal_list_lock);
1108 }
1109 EXPORT_SYMBOL_GPL(thermal_cooling_device_update);
1110
1111 /**
1112  * thermal_cooling_device_unregister - removes a thermal cooling device
1113  * @cdev:       the thermal cooling device to remove.
1114  *
1115  * thermal_cooling_device_unregister() must be called when a registered
1116  * thermal cooling device is no longer needed.
1117  */
1118 void thermal_cooling_device_unregister(struct thermal_cooling_device *cdev)
1119 {
1120         struct thermal_zone_device *tz;
1121
1122         if (!cdev)
1123                 return;
1124
1125         mutex_lock(&thermal_list_lock);
1126
1127         if (!thermal_cooling_device_present(cdev)) {
1128                 mutex_unlock(&thermal_list_lock);
1129                 return;
1130         }
1131
1132         list_del(&cdev->node);
1133
1134         /* Unbind all thermal zones associated with 'this' cdev */
1135         list_for_each_entry(tz, &thermal_tz_list, node) {
1136                 if (tz->ops->unbind)
1137                         tz->ops->unbind(tz, cdev);
1138         }
1139
1140         mutex_unlock(&thermal_list_lock);
1141
1142         device_unregister(&cdev->device);
1143 }
1144 EXPORT_SYMBOL_GPL(thermal_cooling_device_unregister);
1145
1146 static void bind_tz(struct thermal_zone_device *tz)
1147 {
1148         int ret;
1149         struct thermal_cooling_device *pos = NULL;
1150
1151         if (!tz->ops->bind)
1152                 return;
1153
1154         mutex_lock(&thermal_list_lock);
1155
1156         list_for_each_entry(pos, &thermal_cdev_list, node) {
1157                 ret = tz->ops->bind(tz, pos);
1158                 if (ret)
1159                         print_bind_err_msg(tz, pos, ret);
1160         }
1161
1162         mutex_unlock(&thermal_list_lock);
1163 }
1164
1165 static void thermal_set_delay_jiffies(unsigned long *delay_jiffies, int delay_ms)
1166 {
1167         *delay_jiffies = msecs_to_jiffies(delay_ms);
1168         if (delay_ms > 1000)
1169                 *delay_jiffies = round_jiffies(*delay_jiffies);
1170 }
1171
1172 int thermal_zone_get_crit_temp(struct thermal_zone_device *tz, int *temp)
1173 {
1174         int i, ret = -EINVAL;
1175
1176         if (tz->ops->get_crit_temp)
1177                 return tz->ops->get_crit_temp(tz, temp);
1178
1179         if (!tz->trips)
1180                 return -EINVAL;
1181
1182         mutex_lock(&tz->lock);
1183
1184         for (i = 0; i < tz->num_trips; i++) {
1185                 if (tz->trips[i].type == THERMAL_TRIP_CRITICAL) {
1186                         *temp = tz->trips[i].temperature;
1187                         ret = 0;
1188                         break;
1189                 }
1190         }
1191
1192         mutex_unlock(&tz->lock);
1193
1194         return ret;
1195 }
1196 EXPORT_SYMBOL_GPL(thermal_zone_get_crit_temp);
1197
1198 /**
1199  * thermal_zone_device_register_with_trips() - register a new thermal zone device
1200  * @type:       the thermal zone device type
1201  * @trips:      a pointer to an array of thermal trips
1202  * @num_trips:  the number of trip points the thermal zone support
1203  * @mask:       a bit string indicating the writeablility of trip points
1204  * @devdata:    private device data
1205  * @ops:        standard thermal zone device callbacks
1206  * @tzp:        thermal zone platform parameters
1207  * @passive_delay: number of milliseconds to wait between polls when
1208  *                 performing passive cooling
1209  * @polling_delay: number of milliseconds to wait between polls when checking
1210  *                 whether trip points have been crossed (0 for interrupt
1211  *                 driven systems)
1212  *
1213  * This interface function adds a new thermal zone device (sensor) to
1214  * /sys/class/thermal folder as thermal_zone[0-*]. It tries to bind all the
1215  * thermal cooling devices registered at the same time.
1216  * thermal_zone_device_unregister() must be called when the device is no
1217  * longer needed. The passive cooling depends on the .get_trend() return value.
1218  *
1219  * Return: a pointer to the created struct thermal_zone_device or an
1220  * in case of error, an ERR_PTR. Caller must check return value with
1221  * IS_ERR*() helpers.
1222  */
1223 struct thermal_zone_device *
1224 thermal_zone_device_register_with_trips(const char *type, struct thermal_trip *trips, int num_trips, int mask,
1225                                         void *devdata, struct thermal_zone_device_ops *ops,
1226                                         const struct thermal_zone_params *tzp, int passive_delay,
1227                                         int polling_delay)
1228 {
1229         struct thermal_zone_device *tz;
1230         int id;
1231         int result;
1232         struct thermal_governor *governor;
1233
1234         if (!type || strlen(type) == 0) {
1235                 pr_err("No thermal zone type defined\n");
1236                 return ERR_PTR(-EINVAL);
1237         }
1238
1239         if (strlen(type) >= THERMAL_NAME_LENGTH) {
1240                 pr_err("Thermal zone name (%s) too long, should be under %d chars\n",
1241                        type, THERMAL_NAME_LENGTH);
1242                 return ERR_PTR(-EINVAL);
1243         }
1244
1245         /*
1246          * Max trip count can't exceed 31 as the "mask >> num_trips" condition.
1247          * For example, shifting by 32 will result in compiler warning:
1248          * warning: right shift count >= width of type [-Wshift-count- overflow]
1249          *
1250          * Also "mask >> num_trips" will always be true with 32 bit shift.
1251          * E.g. mask = 0x80000000 for trip id 31 to be RW. Then
1252          * mask >> 32 = 0x80000000
1253          * This will result in failure for the below condition.
1254          *
1255          * Check will be true when the bit 31 of the mask is set.
1256          * 32 bit shift will cause overflow of 4 byte integer.
1257          */
1258         if (num_trips > (BITS_PER_TYPE(int) - 1) || num_trips < 0 || mask >> num_trips) {
1259                 pr_err("Incorrect number of thermal trips\n");
1260                 return ERR_PTR(-EINVAL);
1261         }
1262
1263         if (!ops) {
1264                 pr_err("Thermal zone device ops not defined\n");
1265                 return ERR_PTR(-EINVAL);
1266         }
1267
1268         if (num_trips > 0 && !trips)
1269                 return ERR_PTR(-EINVAL);
1270
1271         if (!thermal_class)
1272                 return ERR_PTR(-ENODEV);
1273
1274         tz = kzalloc(sizeof(*tz), GFP_KERNEL);
1275         if (!tz)
1276                 return ERR_PTR(-ENOMEM);
1277
1278         if (tzp) {
1279                 tz->tzp = kmemdup(tzp, sizeof(*tzp), GFP_KERNEL);
1280                 if (!tz->tzp) {
1281                         result = -ENOMEM;
1282                         goto free_tz;
1283                 }
1284         }
1285
1286         INIT_LIST_HEAD(&tz->thermal_instances);
1287         ida_init(&tz->ida);
1288         mutex_init(&tz->lock);
1289         id = ida_alloc(&thermal_tz_ida, GFP_KERNEL);
1290         if (id < 0) {
1291                 result = id;
1292                 goto free_tzp;
1293         }
1294
1295         tz->id = id;
1296         strscpy(tz->type, type, sizeof(tz->type));
1297
1298         if (!ops->critical)
1299                 ops->critical = thermal_zone_device_critical;
1300
1301         tz->ops = ops;
1302         tz->device.class = thermal_class;
1303         tz->devdata = devdata;
1304         tz->trips = trips;
1305         tz->num_trips = num_trips;
1306
1307         thermal_set_delay_jiffies(&tz->passive_delay_jiffies, passive_delay);
1308         thermal_set_delay_jiffies(&tz->polling_delay_jiffies, polling_delay);
1309
1310         /* sys I/F */
1311         /* Add nodes that are always present via .groups */
1312         result = thermal_zone_create_device_groups(tz, mask);
1313         if (result)
1314                 goto remove_id;
1315
1316         /* A new thermal zone needs to be updated anyway. */
1317         atomic_set(&tz->need_update, 1);
1318
1319         result = dev_set_name(&tz->device, "thermal_zone%d", tz->id);
1320         if (result) {
1321                 thermal_zone_destroy_device_groups(tz);
1322                 goto remove_id;
1323         }
1324         result = device_register(&tz->device);
1325         if (result)
1326                 goto release_device;
1327
1328         /* Update 'this' zone's governor information */
1329         mutex_lock(&thermal_governor_lock);
1330
1331         if (tz->tzp)
1332                 governor = __find_governor(tz->tzp->governor_name);
1333         else
1334                 governor = def_governor;
1335
1336         result = thermal_set_governor(tz, governor);
1337         if (result) {
1338                 mutex_unlock(&thermal_governor_lock);
1339                 goto unregister;
1340         }
1341
1342         mutex_unlock(&thermal_governor_lock);
1343
1344         if (!tz->tzp || !tz->tzp->no_hwmon) {
1345                 result = thermal_add_hwmon_sysfs(tz);
1346                 if (result)
1347                         goto unregister;
1348         }
1349
1350         mutex_lock(&thermal_list_lock);
1351         list_add_tail(&tz->node, &thermal_tz_list);
1352         mutex_unlock(&thermal_list_lock);
1353
1354         /* Bind cooling devices for this zone */
1355         bind_tz(tz);
1356
1357         INIT_DELAYED_WORK(&tz->poll_queue, thermal_zone_device_check);
1358
1359         thermal_zone_device_init(tz);
1360         /* Update the new thermal zone and mark it as already updated. */
1361         if (atomic_cmpxchg(&tz->need_update, 1, 0))
1362                 thermal_zone_device_update(tz, THERMAL_EVENT_UNSPECIFIED);
1363
1364         thermal_notify_tz_create(tz->id, tz->type);
1365
1366         return tz;
1367
1368 unregister:
1369         device_del(&tz->device);
1370 release_device:
1371         put_device(&tz->device);
1372         tz = NULL;
1373 remove_id:
1374         ida_free(&thermal_tz_ida, id);
1375 free_tzp:
1376         kfree(tz->tzp);
1377 free_tz:
1378         kfree(tz);
1379         return ERR_PTR(result);
1380 }
1381 EXPORT_SYMBOL_GPL(thermal_zone_device_register_with_trips);
1382
1383 struct thermal_zone_device *thermal_tripless_zone_device_register(
1384                                         const char *type,
1385                                         void *devdata,
1386                                         struct thermal_zone_device_ops *ops,
1387                                         const struct thermal_zone_params *tzp)
1388 {
1389         return thermal_zone_device_register_with_trips(type, NULL, 0, 0, devdata,
1390                                                        ops, tzp, 0, 0);
1391 }
1392 EXPORT_SYMBOL_GPL(thermal_tripless_zone_device_register);
1393
1394 void *thermal_zone_device_priv(struct thermal_zone_device *tzd)
1395 {
1396         return tzd->devdata;
1397 }
1398 EXPORT_SYMBOL_GPL(thermal_zone_device_priv);
1399
1400 const char *thermal_zone_device_type(struct thermal_zone_device *tzd)
1401 {
1402         return tzd->type;
1403 }
1404 EXPORT_SYMBOL_GPL(thermal_zone_device_type);
1405
1406 int thermal_zone_device_id(struct thermal_zone_device *tzd)
1407 {
1408         return tzd->id;
1409 }
1410 EXPORT_SYMBOL_GPL(thermal_zone_device_id);
1411
1412 struct device *thermal_zone_device(struct thermal_zone_device *tzd)
1413 {
1414         return &tzd->device;
1415 }
1416 EXPORT_SYMBOL_GPL(thermal_zone_device);
1417
1418 /**
1419  * thermal_zone_device_unregister - removes the registered thermal zone device
1420  * @tz: the thermal zone device to remove
1421  */
1422 void thermal_zone_device_unregister(struct thermal_zone_device *tz)
1423 {
1424         int tz_id;
1425         struct thermal_cooling_device *cdev;
1426         struct thermal_zone_device *pos = NULL;
1427
1428         if (!tz)
1429                 return;
1430
1431         tz_id = tz->id;
1432
1433         mutex_lock(&thermal_list_lock);
1434         list_for_each_entry(pos, &thermal_tz_list, node)
1435                 if (pos == tz)
1436                         break;
1437         if (pos != tz) {
1438                 /* thermal zone device not found */
1439                 mutex_unlock(&thermal_list_lock);
1440                 return;
1441         }
1442         list_del(&tz->node);
1443
1444         /* Unbind all cdevs associated with 'this' thermal zone */
1445         list_for_each_entry(cdev, &thermal_cdev_list, node)
1446                 if (tz->ops->unbind)
1447                         tz->ops->unbind(tz, cdev);
1448
1449         mutex_unlock(&thermal_list_lock);
1450
1451         cancel_delayed_work_sync(&tz->poll_queue);
1452
1453         thermal_set_governor(tz, NULL);
1454
1455         thermal_remove_hwmon_sysfs(tz);
1456         ida_free(&thermal_tz_ida, tz->id);
1457         ida_destroy(&tz->ida);
1458
1459         mutex_lock(&tz->lock);
1460         device_del(&tz->device);
1461         mutex_unlock(&tz->lock);
1462
1463         kfree(tz->tzp);
1464
1465         put_device(&tz->device);
1466
1467         thermal_notify_tz_delete(tz_id);
1468 }
1469 EXPORT_SYMBOL_GPL(thermal_zone_device_unregister);
1470
1471 /**
1472  * thermal_zone_get_zone_by_name() - search for a zone and returns its ref
1473  * @name: thermal zone name to fetch the temperature
1474  *
1475  * When only one zone is found with the passed name, returns a reference to it.
1476  *
1477  * Return: On success returns a reference to an unique thermal zone with
1478  * matching name equals to @name, an ERR_PTR otherwise (-EINVAL for invalid
1479  * paramenters, -ENODEV for not found and -EEXIST for multiple matches).
1480  */
1481 struct thermal_zone_device *thermal_zone_get_zone_by_name(const char *name)
1482 {
1483         struct thermal_zone_device *pos = NULL, *ref = ERR_PTR(-EINVAL);
1484         unsigned int found = 0;
1485
1486         if (!name)
1487                 goto exit;
1488
1489         mutex_lock(&thermal_list_lock);
1490         list_for_each_entry(pos, &thermal_tz_list, node)
1491                 if (!strncasecmp(name, pos->type, THERMAL_NAME_LENGTH)) {
1492                         found++;
1493                         ref = pos;
1494                 }
1495         mutex_unlock(&thermal_list_lock);
1496
1497         /* nothing has been found, thus an error code for it */
1498         if (found == 0)
1499                 ref = ERR_PTR(-ENODEV);
1500         else if (found > 1)
1501         /* Success only when an unique zone is found */
1502                 ref = ERR_PTR(-EEXIST);
1503
1504 exit:
1505         return ref;
1506 }
1507 EXPORT_SYMBOL_GPL(thermal_zone_get_zone_by_name);
1508
1509 static int thermal_pm_notify(struct notifier_block *nb,
1510                              unsigned long mode, void *_unused)
1511 {
1512         struct thermal_zone_device *tz;
1513
1514         switch (mode) {
1515         case PM_HIBERNATION_PREPARE:
1516         case PM_RESTORE_PREPARE:
1517         case PM_SUSPEND_PREPARE:
1518                 atomic_set(&in_suspend, 1);
1519                 break;
1520         case PM_POST_HIBERNATION:
1521         case PM_POST_RESTORE:
1522         case PM_POST_SUSPEND:
1523                 atomic_set(&in_suspend, 0);
1524                 list_for_each_entry(tz, &thermal_tz_list, node) {
1525                         thermal_zone_device_init(tz);
1526                         thermal_zone_device_update(tz,
1527                                                    THERMAL_EVENT_UNSPECIFIED);
1528                 }
1529                 break;
1530         default:
1531                 break;
1532         }
1533         return 0;
1534 }
1535
1536 static struct notifier_block thermal_pm_nb = {
1537         .notifier_call = thermal_pm_notify,
1538 };
1539
1540 static int __init thermal_init(void)
1541 {
1542         int result;
1543
1544         result = thermal_netlink_init();
1545         if (result)
1546                 goto error;
1547
1548         result = thermal_register_governors();
1549         if (result)
1550                 goto unregister_netlink;
1551
1552         thermal_class = kzalloc(sizeof(*thermal_class), GFP_KERNEL);
1553         if (!thermal_class) {
1554                 result = -ENOMEM;
1555                 goto unregister_governors;
1556         }
1557
1558         thermal_class->name = "thermal";
1559         thermal_class->dev_release = thermal_release;
1560
1561         result = class_register(thermal_class);
1562         if (result) {
1563                 kfree(thermal_class);
1564                 thermal_class = NULL;
1565                 goto unregister_governors;
1566         }
1567
1568         result = register_pm_notifier(&thermal_pm_nb);
1569         if (result)
1570                 pr_warn("Thermal: Can not register suspend notifier, return %d\n",
1571                         result);
1572
1573         return 0;
1574
1575 unregister_governors:
1576         thermal_unregister_governors();
1577 unregister_netlink:
1578         thermal_netlink_exit();
1579 error:
1580         mutex_destroy(&thermal_list_lock);
1581         mutex_destroy(&thermal_governor_lock);
1582         return result;
1583 }
1584 postcore_initcall(thermal_init);